Cartridge syringe



July 28, 1953 F. E. BROWN CARTRIDGE SYRINGE 5 Sheets-Sheet 1 Filed Sept. 21, 1950 FIGJ "funn-lin.; M

w R.R m8 mi VK mm., R Fm Y B ATTORNE Y July 28, 1953 F. E. BRowN CARTRIDGE SYRINGE 5 Sheets-Sheet 2 Filed Sept. 21 1950 FIG.9

F IGJO a) f//S l# 4 w Am. F

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N w RR w8 me. VK mN m F ATTORNEY July 28, 1953 F, E, BROWN `2,646,798

CARTRIDGE SYRINGE Filed sept. 21, 1950 5 Sheets-sheet 5 FlGJe FIG.2O

' INVENTOR. FRANK E. BROWN ATTORNEY Patented July 28, 1953 CARTRIDGE SYRINGE v Frank Brown, Burbank, Calif.

Application September 21, 1950, Serial No. 186,024

7 Claims.

This invention relates to, and has for its object the provision of, improved cartridge syringes (a cartridge syringe being an injection device comprising a cartridge containing the medicament, and a syringe adapted to receive and activate the cartridge to inject the medicament).

By this invention there is provided .improved cartridge syringes which: do not require sterilization of the outside of the pierceable stopper of the cartridge before use; include simple means for aspiration (not involving a double-cell, aspirating test solution, and special stopper); (preferably) do not require a double-pointed hollow needle-whose stopper-piercing end must be resharpened and checked for straightness-but utilize an ordinary hypodermic needle (single point on hub), thus permitting use of any desired gage or length of needle as well as re-use of the needle after sterilization; and have other advantages which will be clear from the detailed description of various embodiments thereof given hereinafter. I

The improved cartridge syringes of this invention essentially comprise two units, which when assembled and (where necessary) fitted Witha hypodermic needle provide 'an operativehinjection device, one of these units (cap-cartridge, or cartridge-adapter) being discarded after use, and the other (syringe body) being either discarded (when unexpensively constructed for that purpose, e. g., of molded plastic) or. re-used with other cap-cartridge units (in which case the syringe body may be of more permanent construction and materials, e. g., of metal).

The cap-cartridge unit of the cartridgesyringes cf this invention essentially comprises: (A) 'a cap, in the form of a tubular body walled at one end, adapted to be rigidly connected with a syringe body, and having a passage through the walled end to the inside of the tubular body; (B)l a medicament-containing cartridge having a slidable stopper at one end and a pierceable stopper at the other, the latter end being received in and telescopically connected with 'the tubular loody of the cap; and (C) a removableV cover closing said passage; the connection between the (cartridge and cap being such that movement of the cartridge away from the walled end of the cap provides a reduced-pressure chamber therebetween.

The syringe body unit of the cartridge-syringes of this invention essentially comprises a hollow 'body adapted to receive a portion of the cartridge 'of the cap-cartridge unit therein and having means for rigidly connecting it with the cap of the cap-cartridge unit, and a plunger slidably 'mounted therein and adapted to operate the slid- :able stopper of the cartridge. f

In the preferred embodiments of this invention, the ,cap-cartridge unit essentially .cem-

(Cl. 12S-218) prises: a medicament-containing cartridge having a slidable stopper at one end and a pierceable stopper at the other, the latter end of the cartridge also being provided with an annular resilient ange;a cap having a needle-hub-engaging extension at oneend and means atthe other end for rigidly connecting it with a syringe body, a passage through the extension Vto the inside of the cap, and a stopper-piercing element mounted inside the cap, the cartridge being connected with the cap by a sliding nt of the resilient flange of the stopper inside the cap, the t being such as to permit longitudinal movement of the cartridge in the cap without substantially admitting passage of air between the flange and the cap wall; and a removable cover on the extension.

The invention will be described in vdetail in connection with the accompanying drawing; wherein: Fig. 1 is a plan view of a cap-cartridge unit embodying the invention; Fig. 2 is a plan View of a syringe body embodying the invention; Fig. 3 is an axial section of the unit shownV in Fig. 1; Fig. 4 is an axial section of the syringe body shown in Fig. 2; Fig. 5 is a part axial section, part plan view of an injection device'formed by the users assembly of the cap-cartridge unit shown in Figs. 1 and 3 (the hub cover being removed) with the syringe body shown in Figs. 2 and 4 and with an ordinary hypodermic needle; Fig. 6 is a schematic view showing the position of the cartridge in the assembly after retraction of'the cartridge to'as'pirate; `Fig.7 is asimilar View showing the position of the cartridge at the start of the actual injection; Fig. 8 is a similar view showing the position of the cartridge and of the slidable stopper therein at the end of the actual injection; Fig. 9 is an axial section of another cap-cartridge unit embodying this invention, its assembly with a syringe bodyv being indicated by broken lines and the cartridge being shown empty for simplicity of illustration; Fig. 10 is a fragmentary plan view of a'cap-'cartridge unit such as shown in Figs. 1 and 3 assembled with a modified syringe-body; Fig. 11 is a part axial section, part plan view of another capcartridge unit embodying the invention; Fig. 12 is a part axial section, part plan view of a syringe body adapted for assembly with the cap-cartridge unit shown in Fig. 11; Fig. 13 is a plan View of a cap for anothercap-cartridge 'unitn embodying the invention; Fig. 14 is a fragmentary axial section of a syringe body adapted for assembly with the cap (and cartridge) shown in Fig. 13; Fig. 15 is a part axial section, part plan view of another cap-cartridge unit embodying the invention; Fig. 16 is an axial section of another cap-cartridge unit embodying the invention, the cartridge being shown empty and without the slidable stopper for simplicity of illustration;

Fig. 17 is an elevation of the'open end of the cap shown in Fig. 16 (with cartridge removed); Fig. 18 is a part axial section, part plan View of another cap-cartridge unit embodying the invention; Fig. 19 is an end View of the unit shown in Fig. 18', with schematic indication of a step in the production of such unit; and Fig. 20 is a part axial section part plan View of another capcartridge unit embodying the invention. [The shapes and proportions of the various elements shown in these gures are illustrative only, and in some cases are deliberately exaggerated for purposes of clarity of illustration] Referring rst to Figs. l and 3, the cap-cartridge unit shown comprises generally a cartridge l, a cap 2 receiving one end ci the cartridge, and a cover 3 on a needle-hub-engaging extension of the cartridge. The cartridge is essentially conventional, and is produced in the conventional manner; thus, it is formed of a tube of glass or equivalent material having Stoppers and of rubber or equivalent material positioned in each end thereof to form a hermetically sealed container for an injectable liquid medicament 6. Stopper il is slidable in the bore of the tube and is provided with the conventional annular grooves (to enhance fit) and with an outwardly-opening threaded recess l adapted to receive a correspondingly threaded element on the syringebody plunger. Stopper 5 has the conventional inwardly-extending recess (to minimize the thickness of rubber to be pierced by an axially- `positioned hollow needle), and a )flanged head il, the diameter of the head being such as to slidably associate the stopper 5 (and hence cartridge) with the substantially cylindrical bore 9 of cap 2.

Cap 2 is of transparent material (e. g., plastic) and has the general shape of an open-ended cylinder. Its bore S terminates in a substantially flat face Ill from which extends an axially-positioned hollow needle Ii having a piercing point I2. The needle il passes through (and is iixed in) the end of wall or the cap and through the integral axial extension thereof i3; the external diameter and taper of the extension corresponding with the internal diameter and taper or the hub of a conventional hypodermic needle ill-I5 (see Fig. 5). Extension I 3 is provided with a frictionally-retained, removable cover 3 of rubber or equivalent material. The other end oi the cap is provided with external (desirably fast) threading I'I; and the cap is of enlarged diameter (and knurled, if desired) at an intermediate point it), providing a handle for assembling the cap with the syringe body.

The frictional hold of slidable stopper ti in the tube of the cartridge should be such that a pull on the stopper can retract the cartridge (i. e., move the cartridge in the cap away from the needle) without substantially moving the stopper in the cartridge (it being noted that stopper 5, by virtue of its iianged head, virtually cannot be pulled into the. cartridge and hence assists in preventing stopper il from being pulled out) but the irictional hold should be insucient to prevent stopper 4 from being pushed into the bore of the cartridge to expel the medicament through the pierced stopper 5. Stopper 5, on the other hand, is held against inward movement by its flanged head, and its frictional hold in the cartridge should be such as to prevent it from being pulled out on retracting the cartridge. The frictional hold 0f the flange 8 (of stopper 5 in the bore of the cap should be suicient to prevent unintended detachment of the cartridge from the cap and to prevent contamination of the aspiration chamber 4 formed by the cap and said flanged stopper; but the rictional hold of the flange should not be such as to prevent its sliding away from the needle I2 to aspirate, and sliding up to face iQ of the cap (the needle li meanwhile piercing the stopper).

The cartridge-cap and cover assembly is prepared under sterile conditions and/or sterilized after assembly, and the assembly packed (either singly, with or without a syringe body, or sevorally) in a suitable container e. g., of cardboard), desirably a container adapted to prevent accidental detachment of the cartridge from the cap during distribution. The portions of the assembly capable of introducing contaminants on injection (i. e., face of stopper 5, needle I I, and aspiration chamber) are substantially hermetically sealed off, and thus remain sterile until use; and those portions are not subject to contamination when associating this unit with the syringe body (which need not be sterile). Removal of cover 3 and attachment of a sterile needle require only the usual technique of avoiding contamination.

As shown in Figs. 2 and e, the syringe body comprises an elongated hollow cylindrical body 26 of plastic or equivalent material, and a plunger 2i of plastic or equivalent material slidably mounted therein. Body 23 has a substantially cylindrical bore 22 between its ends, the diameter being such as to loosely receive cartridge I; its cartridge-receiving end has internal threading 23 corresponding to the external threading on cap 2, enabling rapid joining of the cap with the syringe body into a rigid structure; and its other end has reduced bore '2d through which passes the plunger 2i. The plunger has a rod portion 25 slidable in bore 24 and terminating at its outer end in an enlarged portion 25 shaped to provide a thumb rest; and to its inner end there is (permanently) attached, by tightly threading therein, an element (of metal, for example) having a disc-portion 2i' or larger diameter than bore 24 (hence preventing the plunger from slipping out of the body 28) and a 'threaded axial extension 28 adapted to be engaged with the internal threading in stopper i of the cartridge. Also, body 2G is provided with an external annular flange 2Q intermediate its length, provifing a linger rest for operation of the injection device.

As shown in Fig. 5, the cap-cartridge unit shown in Figs. 1 and 3 is assembled with the syringe body shown in Figs. 2 and 4 and with a hypodermic needle, and the assembly is operated as an injection device as schematically shown in Figs. 6, 7 and 8. In assembling the units, the plunger is rst retracted (beyond the position shown in Fig. 5), the cartridge inserted into the bore of the syringe body and the cap and syringebody threads engaged; the threaded element on the plunger rod is then engaged with the threaded stopper in the cartridge; and the cover on the cap extension removed, and a sterile needle attached thereto (by slipping its hub on the extension and twisting).

In using this injection device, the needle is inserted into the patient, and, while holding the unitary cap and syringe body assembly with one hand, the plunger is retracted with the other (cf., Fig. 6. This action pulls the cartridge away from the needle and enlarges the aspiration chamber (cf., 3U in Fig. 5 and 3| in Fig. 6), the reduced pressure causing blood to issue into said chamber ii the needle I5 is positioned in a vein; in that 5, case the needle is repositioned, unless, of course, intravenous administration is desired. The plunger is then pushed into the syringe body, forcing stopper against the needle point i2 and causing the stopper to be pierced; and further pushing on the plunger brings the face of stopper 5 to a stop against inner face l@ of the cap (cf., Fig. 7). Then, further pushing on the plunger causes stopper 4 to slide through the bore of the cartridge, causing the medicament to pass out of the cartridge through needle l I and the attached hypodermic needle into the patient (ci, Fig. 8). Alternatively, the cartridge is nrst pushed towards needle point l2 and stopper 5 pierced, and a drop of the medicament expressed through needle l5 (conventional technique, to assure there is no needle blockage) then the needle I5 is inserted into the patient, and the cartridge retracted to the position shown in Fig. 6, to aspirate; and if the needle is properly positioned, the cartridge is again pushed forward (needle point I2 re-entering stopper 5) and the medicament injected.

The alternative embodiment of the invention shown in Fig. 9 utilizes the identical cap as the unit illustrated in Fig. 2, but the cap is associated with a cartridge of the two-cell, by-pass type (which is the subject matter of my application Serial No. 109,430, filed August 10, 1949, now Patent No. 2,549,417, dated April 17, 1951). For the purposes of its utilization in conjunction with the present invention, said cartridge need be only generally described. It is formed of a tube 32 of glass or equivalent material having Stoppers 33 and 34 of rubber or equivalent material positioned in each end thereof to form a hermeticallysealed container, and a partition 35 of rubber or equivalent material positioned between Stoppers 33 and 34 to provide two noncommunicating chambers 35 and 31. Chamber 36 contains a medicament (of the type which is desirably not added to the diluent until just before use), and chamber 31 the diluent therefor. Stopper 33 (like stopper 5 in the embodiment shown in Fig. 3) has an inwardly-extending recess and flanged head; and stopper 34 (like stopper 4) is slidable in the bore of the tube and has a threaded recess to receive the threaded element on the syringebody plunger. Y Partition 35 is slidable in the bore of the tube; and adjacent said partition, in the chamber 36, the tube has a longitudinally-extending deformation 38 longer than partition 35, the deformation being such that when the partition 35 moves to the position indicated by dotted lines, the diluent can by-pass the partition by means of said deformation.

The cap-cartridge unit shown in Fig. 9 is adapted to be used with a syringe body of the same general type as that shown in Figs.'2 and 4, such assembly being indicated by broken lines. Necessarily, the body portion and rod portion will have to be made longerrthan their counterparts in the syringe body shown in Figs. 2 and 4J to accommodate the longer cartridge; and the same elongated syringe body obviously may be used with either the simple (short) cartridge of Figs. land 3, or the by-pass (elongated) cartridge shown in Fig. 9.

' In the embodiment of the invention shown in Fig. 10, the cap-cartridge unit is the same as shown in Figs. l and 3, and the syringe body is the same as that shown in Figs. 2 and 4-except thatthe body 39 is provided with two (or more) substantially diametricallyfpositioned, longitudinally-extending slots (of which one, 40, is shown).

These Yslots are so positioned and/or 'of such length as to expose part of 'cartridge I when the cartridge is in the aspiration-beginning position (of. Fig. 5). This embodiment of the invention enables aspiration by retracting the plunger as described hereinbefore; or optionally, lby holding cap 2 with iingers of one hand, gripping the syringe body and cartridge (through the slots) with the fingers of theother hand, androtating the syringe body (in the unthreading direction) while holding the cap stationary, the cartridge following the motion of the syringe body and hence being retracted in the aspiration chamber. Alternatively, the threaded recess in the slidable stopper of the cartridge and the threaded element on the plunger rod may be omitted, and aspiration accomplished solely by the (partial) unthreading operation described.

The embodiment of the cap-cartridge unit shown in Fig. 11 and the embodiment of the syringe body to be used therewith shown in Fig. 12 correspond generally to the respective units shown in Figs. 3 and 4, the difference being primarily in their adaptation for assembly and aspiration. Thus, the unit shown. in Fig. ll'differs in that: the external'threading 4| thereon is a short turn and relatively slow, and spaced from the annular extension 42; and (desirably) the internal threading in the sliding stopper of the cartridge is omitted. The unit shown in Fig. 12 differs in that: the body 43 has slots therein (one, 44, being shown) similar to those in the syringe body shown in Fig. 10; two sets of internal threading, 45 and 45 (corresponding to the external threading 4I on the cap) are provided in the bore of the body, providing in eiect interrupted threading, the intermediate portion 41 being of such diameter as to slidably receive threading 4l on the cap; and (desirably), the

threaded element on the plunger rod is omitted.

The units shown in Figs. 11 and l2 are assembled by threading (cap) threading 4i through (body) threading 45, and sliding the cap further into the body until threading 4l is adjacent threading 46. Aspiration is then accomplished by gripping the cap with the ingers of one hand, and the syringe body and cartridge (through the slots) with the lingers of the other hand, and pulling the syringe body and cartridge away from the (stationary) cap, threading 45 then acting as a stop to prevent the two units from being pulled apart. The syringe body and cartridge are then returned to initial position, and threading 46 engaged with threading 4| to provide a rigid assembly.

Alternatively, the two sets of threading may be provided on the outside of the cap (i. e., additional threading provided adjacent extension 42) and only one set of internal threading 45 provided in the bore of the syringe body, the assembly of the units and operation being effected in the same manner as described in connection with Figs. 1l and 12.

f The cap shown in Fig. 13 and the syringe body shown in Fig. 14 correspond generally t0 the cap and syringe body shown respectively in Figs. 1-3 and 2 4, the dierence being in their adaptation for assembly. Thus, in the cap shown in Fig. 13, the external threading isl replaced by substantially diametrically positioned lugs 41 and 48; and the syringe body shown in Fig. 14 is provided with bayonet slots adapted to receive these lugs (only one slot, 49, being shown). The cap is assembled with the syringe body by iirst inserting the cartridge associated with the cap into the 7, syringe body, then pushing the lugs of the cap into the longitudinally-extending arms of the bayonet slots, and finally relatively-rotating the Cap and syringe body to force the lugs into the circumferentially-extending arms of the bayonet slots. Preferably, the bayonet slots are of such shape and in such position that the cap is locked in position, i. e., offers substantial resistance to relative rotation of the parts for separation.

In the cap-cartridge unit shown in Fig. 15, the fixed hollow needle (for piercing the cartridge Stopper) is replaced by a floating needle, obvating the relatively-expensive operation of fixing the needle in the cap. The end wall and extension of the cap are provided with a passage 50 adapted to slidably receive a single-pointed hollow needle i having a disc 52 fixed thereon intermediate its length (e. g., by staking). The non-pointed end of the needle is normally positioned so as to extend beyond the end of the extension on the cap, the extension cover 53 being suitably modified to accommodate this extra length. Such needle is loosely assembled with the cap by merely positioning it through the open end of the cap before the cartridge is inserted, the cartridge retaining the floating needle in the cap.

In operation, engagement of the hub of a conventional hypodermic needle with the extension causes the floating needle to move toward and pierce the cartridge stopper; the aspiration and injection operation being the same as that described in connection with the embodiment shown in Figs. 1-5.

In the embodiment shown in Figs. 1G and i7, both a fixed and floating needle in the cap are dispensed with. The external form of cap Erl conforms generally to that of the cap shown in Figs, 1 and S-except for the more readily illustrated lugs replacing the threading, as in Fig. 13. The end wall 55 and hub-engaging extension 5S are provided with a passage 5l; and adjacent the entrance of this passageway into the cap, there is provided (p-referably integrally, by molding) a piercing point 5S. rIhe cartridge shown conforms generally to that of the cap-cartridge unit shown in Fig. S-except that the flanged `pierceable stopper 5S (of rubber or equivalent flexible materia-l) is formed with a relatively thin, internallydomed central portion Ei). Preferably (as shown more clearly in Fig. 17) the cutting point 58 is in the form of an off-center sliver adapted to cut a flap in the pierceable stopper 59, and thereby provide an opening overlapping the entrance of passage 5l. For distribution of this embodiment, the cartridge may be pushed into the cap until the stopper is positioned against the end `wall of the cap, thus providing a more stable unit (i. e., more securely engaged, providing a more extensive seal between the stopper flange and the cap, and obviating any possibility of the stopper being accidentally pierced during distribution).

The cap-cartridge unit shown in Figs. 16 and 17 is assembled with a syringe body such as shown in Figs. 2 and 4 (but having bayonet slots in place of threading), the protective cover 5I is removed, and a conventional hypodermic need-le attached to extension 56. Then, after aspiration as described hereinbefore (by retraction of the cartridge in the cap), the cartridge is pushed back into the position shown in Fig. 16; pushing on the slidable stopper of the cartridge then urges the domed portion 6i) of the pierceable stopper to flex outwardly, causing it to be pierced; and

further pushing on the slidable stopper causes the medicament to leave the cartridge and be injected (contact of the medicament with the walls of the chamber formed by the domed stopper and cap being immaterial, since that chamber has been pre-sterilized and maintained sterile).

In the embodiment shown in Figs. 18 and 19, means are provided for preventing accidental or undesired detachment of the cartridge from the cap (especially for preventing potentially dangerous re-use of the cap by re-assemb-ling it with another cartridge). The cap shown conforms generally to that shown in Figs. 1 and 3 (with lugs in place of threading) -except that the open end of the cap is provided with two or more (four being shown) inwardly-extending deformations 62, 63, 613, 55, extending substantially to the outer surface of the cartridge. These deformations are formed, after insertion of the cartridge, by suitably supporting the cap-cartridge unit and bringing appropriately-shaped heated tools (illustrated by broken lines in Fig. 19) against the outer surface of the (thermoplastic) cap, and moving them towards the center until the desired deformations are formed. The cartridge in this embodiment conforms generally with that shown in Fig, S-except that (preferably) the pierceable stopper end thereof is provided with an annular bead 5S of a diameter less than the internal diameter of the cap but suicient to prevent its passing the deformed portion of the cap.

In the embodiment shown in Fig. 20, no stopper piercing element is carried by the cap, sacrificing certain of the advantages of this invention 'but resulting in further simplification. The cartridge is the same as that shown in Fig. 3; and the cap differs from that shown in Fig. 3 in that the needle is omitted, and the extension l is provided with external threading 63 (preferably tapered) and with a passageway 69 leading through the end wall of the cap and of suicient diameter to slidably receive the piercing end of a double-pointed hollow needle. rIhe extension is closed (during distribution of the unit) by a threaded cap lc. In using this embodimentI the cap-cartridge unit is assembled with a syringe body, cap 'iii removed and replaced by a double pointed needle having a threaded-hub engaging threading 68, and the cartridge syringe then operated in the same manner as that shown in Fig. 5, the double-pointed needle being of course reusable. Alternatively, the extension 6'1 may be omitted, and the passageway through the end wall enlarged and internally threaded (preferably flared) to receive an externally threaded member which is fixed intermediate the ends of a double pointed needle.

Other embodiments of the invention (including combinations of various features of the different embodiments described hereinbefore) will readily occur to those skilled in the art. A number of these are generally described hereinafter, detailed description and illustration by drawing being deemed unnecessary in View of the large number and representative nature of the embodiments shown in the drawing and described in detail hereinbefore.

Again sacrificing some of the advantages of the invention but with attendant simplication, the cap may have fixed therein a double-ended needle, with a cover on the extension enclosing the outer needle and thus maintaining it and the aspiration chamber sterile.

The slidable connection of the cartridge with the ycap may be effected in the following additional ways, inter alia: by means of a ring of resilient material (separate from the pierceable stopper) gripping the cartridge and having a sliding t in the cap; by means of a ring of circular cross section gripping the cartridge and adapted to slide or roll in the cap as the cartridge is moved longitudinally in the cap; and by means of a substantially sliding iit between the cartridge itself and the cap, with an annular band of lubricant therebetween.

The needle extending into the capfor piercing the cartridge stopper (cf. Fig. 3) may be xed in the cap in the conventional manner, e. g. by molding the plastic cap around it. In such case, the non-piercing end of the needle should preferably extend beyond the end of the hub-engaging extension, to prevent any plastic entering the needle during the molding operation.

The various features shown and/or described hereinbefore may be combined in various other ways to provide still other embodiments of the invention. Thus, the by-pass cartridge shown in Fig. 9 may be made a component of the modied cap-cartridge unit shown in Figs. 1l, 15, 18 and 20; and the slots shown in Fig. 10 may be provided in the syringe body shown in Figs. 2, 4 and 5, the threaded extension on the rod and threaded recess in the slidable stopper being then omitted, and aspiration being accomplished by merely retracting the cartridge with the ngers through the slots.

The invention may be variously otherwise embodied within the scope of the appended claims.

I claim:

1. A cartridge syringe comprising a syringe body and a cap-cartridge unit assembled therewith: said syringe body essentially comprising a hollow body adapted to receive a portion of the cartridge of the cap-cartridge unit therein and having means for rigidly connecting it with the cap of the cap-cartridge unit, and a plunger slidably mounted therein and adapted to operate the slidable stopper of the cartridge: said cap-cartridge unit essentially comprising (A) a cap, in the form of a tubular body walled at one end, adapted to be rigidly connected with the syringe body, and having a passage through the walled end to the inside of the tubular body, (B) a medicament-containing cartridge having a slidable stopper at one end and a pierceable stopper at the other, the latter end being received in and telescopically connected with the tubular body of the cap, and (C) a removable cover closing said passage; the connection between the cartridge and cap being such that movement of the cartridge away from the walled end f the cap provides a reduced-pressure chamber therebetween.

2. A cap-cartridge unit for assembly with a syringe body to provide a cartridge syringe, essentially comprising: (A) a cap, in the form of a tubular body walled at one end, adapted to be rigidly connected with a syringe body, and having a passage through the walled end to the inside of thetubularbody; (B) a medicamentcontaining cartridge having a slidable stopper at one end and a pierceable stopper at the other, the latter end being received in and telescopically connected with the tubular body of the cap; and (C) a removable cover closing said passage; the connection between the cartridge and cap being such that movement of the cartridge away from the walled end of the cap provides a reduced pressure chamber therebetween.

3. A cartridge syringe comprising a syringe body and a cap-cartridge unit assembled therewith; said syringe body essentially comprising a hollow body adapted to receive a portion of the cartridge therein and having means at one end for rigidly connecting it with the cap of the cap-cartridge unit, and a plunger slidably mounted therein at the other end and adapted to operate the slidable stopper of the cartridge: said cap-cartridge unit essentially comprising a medicament-containing cartridge having a slidable stopper at one end and a pierceable stopper at the other, the latter being provided with an annular resilient flange, a cap having a needlehub-engaging extension at one end and means at the other end for rigidly connecting it with the syringe body, a passage through the extension to the inside of the cap, and a stopperpiercing element mounted inside the cap, the cartridge being connected with the cap by a sliding t of the resilient flange of the stopper inside the cap, the t being such as to permit longitudinal movement of the cartridge in the cap without substantially admitting passage of air between the ange and the cap wall, and a removable cover on the extension.

4. A cap-cartridge unit for assembly with a syringe body to provide a cartridge syringe, es-

sentially comprising a medicament-containing cartridge having a slidable stopper at one end and a pierceable stopper at the other, the latter being provided with an annular resilient flange, a cap having a needle-hub-engaging extension at one end and means at the other end for rigidly connecting it with the syringe body, a passage through the extension to the inside of the cap, and a stopper-piercing element mounted inside the cap, the cartridge being connected with the cap by a. sliding t of the resilient iange of the stopper inside the cap, the flt being such as to permit longitudinal movement of the cartridge in the cap without substantially admitting passage of air `between the flange and the cap wall, and of a removable cover on the extension.

5. A cap-cartridge unit as dened by claim 4, in which the internal diameter of the mouth of the cap is less than the external diameter of the pierceable-stopper end of the cartridge, thus preventing detachment of the cartridge from the cap.

6. A cartridge syringe as dened by claim 3, in which the cap and syringe body are correspondingly threaded to effect a rigid connection therebetween, and in which one of these has its threading interrupted to permit free longitudinal movement of the cap and syringe body relative to each other for the extent of the interruption.

7. A cap-cartridge unit as defined by claim 4,

in which the stopper-piercing element is a singlel pointed hollow needle passing through the extension to the inside of the cap and terminating there in a piercing point.

FRANK E. BROWN.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,388,946 Gfooldv Aug. 30, 1921 1,529,659 Marcy Mar. 17, 1925 1,715,771 MacGregor June 4, 1929 1,929,247 Hein Oct. 3, 1933 2,193,322 Lozier et al Mar. 12, 1940 2,300,070 Smith Oct. 27, 1942 2,542,814 Hoskins Feb. 20, 1951 2.549.417 Brown Apr. 1'7, 1951 

